This is a prospective study of maternal characteristics which affect infant feeding behavior in the first year of life. Factors associated with choice of infant feeding pattern and duration of breast feeding will be investigated. The specific objectives of the study are as follows: (1) to provide detailed information on the change in infant feeding pattern over time; (2) to investigate the underlying meaning of the milk insuficiency syndrome: (3) to investigate the relation between maternal employment and choice and duration of breast feeding; (4) to determine the sociocultural differences in infant feeding between two ethnic groups.